Vertical transistor having a vertical gate structure having a top or upper surface defining a facet formed between a vertical source and a vertical drain

Abstract

Raised structures comprising overlying silicon layers formed by controlled selective epitaxial growth, and methods for forming such raised-structure on a semiconductor substrate are provided. The structures are formed by selectively growing an initial epitaxial layer of mono crystalline silicon on the surface of a semi conductive substrate, and forming a thin film of insulative material over the epitaxial layer. A second epitaxial layer is selectively, grown on the exposed surface of the initial epitaxially grown crystal layer, and a thin insulative film is deposited over the second epitaxial layer. Additional epitaxial layers are added as desired to provide a vertical structure of a desired height comprising multiple layers of single silicon crystals, each epitaxial layer have insulated sidewalls, with the uppermost epitaxial layer also with an insulated top surface.